Height Is Dependent On Diet Quality, Not Genes

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haidut

haidut

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based on the assumption that taller is better

I did not say taller is better. The thread was just to show that one of the most genetically driven feature (according to mainstream medicine) is a lot more malleable than we are led to believe.
 

LiveWire

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If you know the genes responsible for (maximum) height please name them.

Their names are Carl and Helmut, and they live in a person’s heel.

But seriously now, how about some good old empirical evidence. We are three brothers. I’m the oldest, I stand at 6’7”, the middle one is 6’1”, the youngest is 6’7”. Me and the youngest one aren't just the same height, we look alike, we’re clearly on our father’s side of the family. Mostly tall fair skinned people. The middle brother is clearly on the mother’s side, not as tall, darker skinned. So is our youngest sister. Same upbringing, same nutrition, same bed time stories, same school, same air, same everything.

There are million examples like that around us. How can this even be questioned? Are you saying other physical features we inherit from our parents are only thanks to eating exactly like them? :shock:
 
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MarcelZD

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Their names are Carl and Helmut, and they live in a person’s heel.

But seriously now, how about some good old empirical evidence. We are three brothers. I’m the oldest, I stand at 6’7”, the younger one is 6’1”, the youngest is 6’7”. Me and the youngest one aren't just the same height, we look alike, we’re clearly on our father’s side of the family. Mostly tall fair skinned people. The middle brother is clearly on the mother’s side, not as tall, darker skinned. So is our youngest sister. Same upbringing, same nutrition, same bed time stories, same school, same air, same everything.

There are million examples like that around us. How can this even be questioned?

That's not empirical. Moreover height and pigmentation alleles aren't linked.
 

Momado965

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But MGTOW sounds like a different word for incels, with a voluntary pretense.

If you want some **** you gotta play the game. I got the height, I got the hair, I fake muscularity with tighter clothing and sucked in gutt, and my job position creates the illusion of success and wealth. I’m all set.

Could be incels and could be not. Some points mgtow raise cant be argued with, its like the giant pink elephant in the room. I dont blame them tho. All they want is feminine women. I think thats why western men go to eastern europe and asia. The women are actual feminine women over there.
 

Momado965

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Their names are Carl and Helmut, and they live in a person’s heel.

But seriously now, how about some good old empirical evidence. We are three brothers. I’m the oldest, I stand at 6’7”, the middle one is 6’1”, the youngest is 6’7”. Me and the youngest one aren't just the same height, we look alike, we’re clearly on our father’s side of the family. Mostly tall fair skinned people. The middle brother is clearly on the mother’s side, not as tall, darker skinned. So is our youngest sister. Same upbringing, same nutrition, same bed time stories, same school, same air, same everything.

There are million examples like that around us. How can this even be questioned? Are you saying other physical features we inherit from our parents are only thanks to eating exactly like them? :shock:

Could be phermones and hormones that are contagious which then shapes a persons personality and thur physical appearance.
 

LiveWire

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Could be phermones and hormones that are contagious which then shapes a persons personality and thur physical appearance.

Well I’m a natural born ***hole, while my youngest brother is a pretty okay guy, so that personality contagion theory can be hereby safely dismissed.
 

Momado965

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Well I’m a natural born ***hole, while my youngest brother is a pretty okay guy, so that personality contagion theory can be hereby safely dismissed.

Maybe its someone else who’s had an influence on you and you picked it up. You can have a very similar appearance to your father or mother but a very different personality.
 

AlphaCog

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Polynesians/Tongans/Samoan/Fijian? Do they eat a lot of coconut crab(low PUFA)?

Why Polynesians Are Genetically Engineered To Be The Best Football Players In The World

WHY ARE PACIFIC ISLANDERS SO BIG?

There is no legitimate explanation for this, but many believe that generations of farming and strenuous labor required by all males of the family might give us a little more insight as to why these behemoths of athletes exist.

Pacific Islanders are just born big-boned and have frames perfect for any NFL position, especially for linemen down in the trenches.

One theory in physical anthropology is that through ancestral evolution, Polynesians were forced to adapt to cold weather at one stage of their history.

People in cold climates tend to develop larger, lean bodies to store more fat, which would, of course, be a contrast to the warmer tropical environments they live in today. But considering that all Polynesians migrated to islands and were known as extraordinary travelers, this could be where the answer lies.

Other findings show that the Samoan obesity epidemic starts at birth. According to a study conducted by Brown University, weight gain drastically increases 23 percent more in a Samoan boy than the average male American child within the first 15 months of life. This, however, is not confined to just the Samoan populations. Many experts believe that this rise in childhood obesity foreshadows a trend that we can see in the United States.
How paradise became the fattest place in the world
All in the genes?
Some scientists believe that Pacific island populations have evolved to maintain their larger build -- a concept known as the "Thrifty Gene" hypothesis. For this region of the world, the concept is based on the fact Pacific islanders once endured long journeys at sea and those who fared best stored enough energy in the form of fat to survive their journey.
Polynesians: prone to obesity and Type 2 diabetes mellitus but not hyperinsulinaemia.
Tuilagi Family. Tall and thick boned.
tuilagi.jpg
 
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sladerunner69

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Do you know of a gene or group of genes that is responsible for height? Can you share them please? Quite a few groups tried to use computational genomics to predict real-life features based on genes and height has been one of the most sought after predictable features. None of these models has so far managed to do anything useful outside a lab.
So, until I see solid evidence of specific genes linked to height the evidence of the 3 threads above stands - i.e. maximum height depends on quality of environment.
For a bit of anecdotal evidence - basketball player Boban Marjanovic has a height of ‎7 ft. 3′ inches (221 cm). His parents (confirmed by genetic testing) have heights around 5' 8''. Nobody in his lineage is known to have been taller than 6ft and Boban himself does not have a pituitary disorder or another condition explaining his height.
Boban Marjanovic: I'm from another planet, like Superman from Krypton | Eurohoops
"...The Philadelphia 76ers‘ Boban Marjanovic has always towered his opponents – and teammates – with the height of 7’3” (221 cm). People might assume he comes from crazy-tall parents as well but, as in the case of many other ‘giants’, that’s not it. His parents are at 5’6” (168 cm) and 5’9” (175 cm) which isn’t even close, so, how did it happen? ‘The Bobinator’ has got that covered:"
And here are some other things to consider.
Every Gene Affects Every Trait, So Personalized/genomic Medicine Is Doomed
The 'omnigenic' Theory Confirmed Again, Genomic Medicine Likely Useless
Environmental Quality, Not Genetics, Determines Testosterone Levels In Men

Why do some people grow so tall under such terrible conditions, then? For example, blacks tend to be taller than other races. However, most of them live in poverty in the unites states and therefore we could assume that most of the black basketball players did not have access to the quality and quantity of food that whites do. Yet, blacks on average are more than 3 inches taller.

This is clearly an evolutionary adaptation fit for running through the tall brush of the African savannah. Only genes could explain that...
 

Jing

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Food most likely plays a small part in height, most of the height is genes, it is rare to see someone much taller or much smaller than their parents, most people are the same height as parents or slightly shorter or taller.
 

ShotTrue

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I think Haidut is definitely illuminating something, but also a good deal of height potential is passed through DNA

Samoans clean up in contact sports
 

Lydie Baillie

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I posted a few threads in the past demonstrating that gene are likely not the main driver of height, despite the mainstream dogma vehement claiming to the contrary.
Dutch People Gained 20cm Of Height In Just 150 Years
Protein Quality, Not Genes, Determine Male Height

Intelligence and height are often presented as two of the most genetically driven variables of any given human. Below is yet another study demonstrating that switching to a diet containing animal protein allowed the Chinese boys to gain ~10cm on average over a period of just 25 years. Considering the 50% height of a 12-year old Chinese boy in 1985 was around 120cm, the ~10cm gain represents a whopping 8% increase in height. That change is highly statistically significant and cannot be explained by any statistical manipulations as a fluke.

Global meat-eating is on the rise, bringing surprising benefits

"...In the decade to 2017 global meat consumption rose by an average of 1.9% a year and fresh dairy consumption by 2.1% -- both about twice as fast as population growth. Almost four-fifths of all agricultural land is dedicated to feeding livestock, if you count not just pasture but also cropland used to grow animal feed… It is largely through eating more pork and dairy that Chinese diets have come to resemble Western ones, rich in protein and fat. And it is mostly because their diets have altered that Chinese people have changed shape. The average 12-year-old urban boy was nine centimetres taller in 2010 than in 1985, the average girl seven centimetres taller."
Very interesting. Living in Spain for a long number of years, I have personally observed how Spaniards have sprouted up in height in recent years and youngers are notably taller than parents and grandparents, raised on a northern European diet rich in meat and dairy.
 

LiveWire

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Very interesting. Living in Spain for a long number of years, I have personally observed how Spaniards have sprouted up in height in recent years and youngers are notably taller than parents and grandparents, raised on a northern European diet rich in meat and dairy.

So much for the mediterranean diet!

:bs
 

MarcelZD

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While I tend to believe genes play some role in adult height, I wonder about the effects of the intrauterine environment, changes in microbiota and, lastly, epigenetics. Intuitively, I find it unlikely that a woman whose growth was stunted by the environment would have children that reach their maximal potential even under ideal conditions. That might take 2-3 generations.

That's also the major problem with twin studies to assess heredity.
 

Lydie Baillie

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Well, Spain had a very impoverished population up until the 1980s. The average Spanuard relied bread seasoned with olive oil for breakfast, garbanzo and other Spanish beans and rice in weak broth for lunch and dinner. Not exactly the Mediterranean diet.
 
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Do you know of a gene or group of genes that is responsible for height? Can you share them please? Quite a few groups tried to use computational genomics to predict real-life features based on genes and height has been one of the most sought after predictable features. None of these models has so far managed to do anything useful outside a lab.
So, until I see solid evidence of specific genes linked to height the evidence of the 3 threads above stands - i.e. maximum height depends on quality of environment.
For a bit of anecdotal evidence - basketball player Boban Marjanovic has a height of ‎7 ft. 3′ inches (221 cm). His parents (confirmed by genetic testing) have heights around 5' 8''. Nobody in his lineage is known to have been taller than 6ft and Boban himself does not have a pituitary disorder or another condition explaining his height.
Boban Marjanovic: I'm from another planet, like Superman from Krypton | Eurohoops
"...The Philadelphia 76ers‘ Boban Marjanovic has always towered his opponents – and teammates – with the height of 7’3” (221 cm). People might assume he comes from crazy-tall parents as well but, as in the case of many other ‘giants’, that’s not it. His parents are at 5’6” (168 cm) and 5’9” (175 cm) which isn’t even close, so, how did it happen? ‘The Bobinator’ has got that covered:"
And here are some other things to consider.
Every Gene Affects Every Trait, So Personalized/genomic Medicine Is Doomed
The 'omnigenic' Theory Confirmed Again, Genomic Medicine Likely Useless
Environmental Quality, Not Genetics, Determines Testosterone Levels In Men

Haidut, I advise avoiding using of anecdotes to support your claims, it is not very scientific of you and detracts from your credibility. Is your claim that anyone could have become 7'3" with a very high quality environment? Should I provide my anecdote of how my father is 5'10 and mother 5'3 and I ate a protein rich diet in development and am 5'10?
 
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ShotTrue

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Yeh that Bob guy is an interesting case, but for all we know it could simply have been a recessive Gene for height and something chemical. Bone morphogenic protein -7, low aromatase.
I don’t hear that the parents made a special diet where he ate copious amounts of protein to get that tall - and that’s a lot taller than NFL players or 99% of the population
 

ShotTrue

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However I am keeping an open kind on these things. After all genetics is massively over played
 

Literally

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What follows is a detailed criticism of everything that @haidut has stated in this thread, along with a few stray comments.

Why do this? @haidut has made a number of strong claims in this forum, with supporting arguments/narratives. In investigating another such thread recently I found the quality of research and argument to be poor. Again I am finding the quality of the case Haidut makes to be poor in this thread. I think there is value in refuting poor arguments, especially when it comes to someone who makes big claims with a lot of conviction. I think it's especially important for members of an alternative health community not to accept things simply because they are not mainstream.

As a result, I decided to do another point by point response. It takes a lot of words, because in general it takes more time to refute bad arguments than to make them. I still agree the role of genetics is "overplayed" as @ShotTrue described it, in general. But attacking the role of genetics in height was a mistake, as I think many readers will agree, by the end of this, should they dare to venture through it.

I posted a few threads in the past demonstrating that gene are likely not the main driver of height, despite the mainstream dogma vehement claiming to the contrary.
Dutch People Gained 20cm Of Height In Just 150 Years
Protein Quality, Not Genes, Determine Male Height

Okay first up we have a claim that the mainstream view on genes and height is "vehement dogma". In the strictest sense, "dogma" refers to axioms held as uncontestably true, i.e. not subject to debate, evidentiary reasoning, etc. "Vehement" according to Google means "strong feeling; forceful, passionate, or intense." So -- is the mainstream consensus on the role of genes in fact a kind of scientism, enforced through the forceful passion of... statisticians and geneticists? I am going to argue, no... it's more of a calmly held view, held by dispassionate nerds on the basis of strong evidence.

@haidut's chosen title presents a dichotomy (binary) -- "Height Is Dependent On Diet Quality, Not Genes". Because of this I do not understand why @haidut is confused later that someone would take it at face value.

You are making it sound as if I am making it black and white.

I think the charitable thing to do here is credit @haidut with the position that these things are not -- at least not entirely -- mutually exclusive. Early on, he refines his position to "gene (sic) are likely not the main driver of height," which to me affirms that with the chosen title @haidut is speaking "in the main"... rather than in black and white.

Is his implication that the mainstream position is that genes are the main driver of height accurate, then? Largely yes... but also no. Allow me to explain.

The abstract of "Heritability of Adult Body Height: A Comparative Study of Twin Cohorts in Eight Countries," -- https://www.cambridge.org/core/jour...-countries/3EF884AEA534C90F46F95C9FA3944C84-- one paper I'll use as representative of the mainstream view, begins as follows:

"A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect."

This is not quite as strong a statement as the implied mainstream view ("main driver" vs. "major component"), but the paper goes on to claim that heritable traits explain "from 0.68 to 0.84 [of height] when an additive genes/shared environment/unique environment (ACE) model was used" for women. (Interestingly, for men, heritability estimates were higher. This is easily explained in a genetic model by males having a greater ancestral imperative to reach a certain height. Whereas it seems to pose a problem for the view that things are more environmental -- why would environment affect measurably and markedly less for this specific trait?)

In any case, @haidut's fundamental characterization of the mainstream view basically holds, as long as it's not stated too strongly.

But I think it's also good to acknowledge some subtleties. Any time we assign a "percentage" of explanation to genes vs environment, or quantify that, we're relying on specific statistical techniques. On a more realistic level I think everyone acknowledges the interactions are complex.

For example, there is AFAIK nothing much one can do about height later in life, in most cases. To this extent is sees blindingly obvious that the genetic program controls the situation 100%. I am guessing that even @haidut would admit this. ;)

@haidut will go on to imply that examples of environment having a large influence over population or individual heights, in and of themselves, contradict the genetic account. That somehow past and current scientists have not known such things and factored them into the theories. But that isn't at all true. For example, American Colonial soldiers (mostly Englishmen) were known to be about 3" taller than the Royal Marines during the time of the American Revolution. That environmental impacts can have a huge impact on height, a trait thought to be strongly heritable (even before modern genetics, in this case) is not new information, and all theories have developed to take this kind of thing into account.

The main part of the debate is about what is more influential in the distribution of traits within a population. The Scientific American article, https://www.scientificamerican.com/article/how-much-of-human-height/ opens by clarifying this: 'This question can be rephrased as: "How much variation (difference between individuals) in height is attributable to genetic effects and how much to nutritional effects?" The short answer to this question is that about 60 to 80 percent of the difference in height between individuals is determined by genetic factors, whereas 20 to 40 percent can be attributed to environmental effects, mainly nutrition. This answer is based on estimates of the "heritability" of human height: the proportion of the total variation in height due to genetic factors.'

In other words, the mainstream claim that genetics drive height variability isn't incompatible with the claim that environment/nutrition drives the mean. The latter is accepted as assumed. The whole idea is that we're measuring genes response to the environment (and that means it makes sense to separate common/shared environment from unique environment, which is what the aforementioned ACE model does). So the basic approach of saying "see? these starving people are tiny while these well-fed people are huge?" and claiming it's evidence for the "nurture" side argues against a straw man. This idea of variability is a necessary subtlety.

This is underscored in the following interview So is it nature not nurture after all?

'Another problem that Plomin encounters with explaining his findings is that people often confuse group and individual differences – or, to put it another way, the distinction between means and variances. Thus, the average height of northern European males has increased by more than 15cm in the past two centuries. That is obviously due to changes in environment. However, the variation in height between northern European males is down to genetics. The same applies to psychological traits.

'“The causes of average differences,” he says, “aren’t necessarily related to causes of individual differences. So that’s why you can say heritability can be very high for a trait, but the average differences between groups – ethnic groups, gender – could be entirely environmental; for example, as a result of discrimination. The confusion between means and variances is a fundamental misunderstanding.”'

Intelligence and height are often presented as two of the most genetically driven variables of any given human. Below is yet another study demonstrating that switching to a diet containing animal protein allowed the Chinese boys to gain ~10cm on average over a period of just 25 years. Considering the 50% height of a 12-year old Chinese boy in 1985 was around 120cm, the ~10cm gain represents a whopping 8% increase in height. That change is highly statistically significant and cannot be explained by any statistical manipulations as a fluke.

Now @haidut has produced what he pretty clearly means to be a counterxample to the mainstream theory, without directly stating that. But is it much of a counterexample? Beause let's be clear, if less than polite, than Plomin... who is one of the most hardcore genetics guys out there. Plomin just cited an even *bigger* example of a population height change than @haidut. As an example of a common misconception among people who just aren't familiar with the basics of what geneticists like him claim. :eek:

Such examples are utterly non problematic for the mainstream theory of how genes drive height.

Note also that all the population examples discussed so far, while impressive in their own right, still involve deltas of a small percentage of the overall mean height. Is this problematic for a theory that assigns a substantial minority role to environment? Not at all.

At this point @outtherebrother made the following counter-claim:

Genetics determine maximum achievable height, you can reach your genetic max height given that you consume adequate protein throughout development. I highly doubt protein is the only/major component of height determination.

This is quite close to the mainstream view, and incorporates a well-known fact I didn't talk about yet (i.e. that not getting enough is quite problematic and "stunts growth"). But I think it's also slightly misleading to absolutely say that genetics determine the maximum. That's only roughly true, I think. According to the models I've cited and will cite below, environment does have some role on the high end. But it's still a much more accurate statement than any of @haidut's. @haidut responds to it thusly:

Do you know of a gene or group of genes that is responsible for height? Can you share them please? Quite a few groups tried to use computational genomics to predict real-life features based on genes and height has been one of the most sought after predictable features. None of these models has so far managed to do anything useful outside a lab.
So, until I see solid evidence of specific genes linked to height the evidence of the 3 threads above stands - i.e. maximum height depends on quality of environment.

There are a lot of things wrong with this, rapidly packed into succession, so let me try to break it down. First, is it valid to suggest, as this does, that it's necessary to name the genes in order to conclude that heritable factors, rather than environmental ones, predominate height? Not in the slightest! Even folk knowledge has historically recognized height as one of the more heritable traits, e.g. in villages where people commonly ate the same food and lived the same way, heights often went with families. Modern twin studies provide much more compelling evidence.

You may recall that @haidut used the Dutch height increase as a supposed counterexample of the mainstream view. As luck would have it, the Wikipedia article on Twin studies -- Twin study - Wikipedia -- presents a mathematical model that includes data on this very Dutch height-boom, and accounts for it. Thus, you can see why @haidut's apparent notion that mere the *existence* of the Dutch height boom somehow poses a problem for mainstream theory is a complete non sequitur. This page explains some about the ACE (Additive Genes / Common Environment / Shared Environment) mode and how it's derived from twin studies, and may be worth a look.

Why 'additive' by the way? We'll get to that. But let's look at the study.

"Genetic and Environmental Contributions to Weight, Height, and BMI from Birth to 19 Years of Age: An International Study of Over 12,000 Twin Pairs"
Genetic and Environmental Contributions to Weight, Height, and BMI from Birth to 19 Years of Age: An International Study of Over 12,000 Twin Pairs
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3275599/pdf/pone.0030153.pdf

The results are summarized in Tables 1 and 2, on pages 6 and 7 of the PDF. For 19 year old males, 71.8% of height was statistically explained by A (Additive Genes in the model). For 19 year old females, it's "just" 60.4%. That is some pretty compelling evidence that fits the mainstream view, and thus poses problems for @haidut's view.

To put this into clearer focus, just look at the identical twins themselves. Identical twins are almost always very close in height. If the idea that diet matters more than genes were true, wouldn't we have lots of examples of identical twins with wildly different heights?

A striking thing in favor of the heritability argument, that emerges in this study is that heritable factors play an *increasing* role over time. That is, their data show that environmental factors matter more right at birth and soon after, then over time they matter less and less.

For a bit of anecdotal evidence - basketball player Boban Marjanovic has a height of ‎7 ft. 3′ inches (221 cm). His parents (confirmed by genetic testing) have heights around 5' 8''. Nobody in his lineage is known to have been taller than 6ft and Boban himself does not have a pituitary disorder or another condition explaining his height.

Is this evidence for or against anything? In short, no. Individual cases don't invalidate statistical methods. Suggesting so is, however, a red flag.

To expand a bit on this... children share 50% of genes with each parent. Which is the same percentage that siblings share. While it's rare for one sibling to be quite tall while another is average height, it's not that rare. This might be worth thinking about later when I talk about the evidence for 'additive' genetics.

... All I am doing is presenting the evidence, which so far favors the environmental influence over genes.

Literally none of the evidence presented so far favors the environmental influence over genes -- except in a trivial sense that no one really argues. The mainstream view for example, has no problem with the concept that environmental factors limit height. Take it to the extreme -- feed a child almost nothing and they will be extremely short. Saying that's evidence against the genetic view is, frankly and simply, a misunderstanding or misconstruction of the mainstream view. It's just as irrelevant as my point earlier about how height can't really be changed after a certain age demonstrating 100% genetic control. Anyone with an understanding of the debate understands that nurture "wins" in the former and genes "win" in the latter case, and that these define extremes in a certain sense. That's taken as a given; it's not the nature of the debate.

So far I have not heard/seen anything about specific genes related to height. If you know the genes responsible for (maximum) height please name them. Did you see my other comment on so many groups trying to arithmetically predict height using even genome-wide associations? None of those attempts worked.

I argued above that it's not necessary to provide direct genetic evidence in order to conclude with confidence that height is largely a heritable trait -- meaning, as the mainstream view actually holds, that much of the *variability* in height is explained by heritable factors, primarily genetics. And it really isn't, but @haidut's suggestion that there is no clear evidence linking specific human genes to height is also dead wrong.

A 2010 study found human genetic data at 180 different genetic loci statistically explained 10 of height in subjects. While height is the product of many separate genes (see below), this is strong evidence that some genes matter more than others. 'Giant' step toward explaining differences in height among people

Fast forward to recently and we have identified genetic variations at over 700 loci collectively accounting for 20% of the overall genetic role. Does the fact that we have "only" got 20% of it so far pose a problem for the genetic argument? No. Does the existence of this invalidate everything @haidut just said in the previous quote? Yes.

Check these threads as well.
Every Gene Affects Every Trait, So Personalized/genomic Medicine Is Doomed
The 'omnigenic' Theory Confirmed Again, Genomic Medicine Likely Useless
Environmental Quality, Not Genetics, Determines Testosterone Levels In Men

Okay, let's wrap it up. Does the fact that many genes affect many traits and vice versa pose a problem for the genetic theory? Nope. Does it pose a problem for the *usefulness* of genetic analysis. That depends -- from the point of view of the popular misconception that there is a single gene for many traits, yes. In reality, it's a mixed bag. The math is harder. That doesn't undermine the genetic theory. And it has already been usefully demonstrated with height that specific genes can contribute disproportionately and that we can find them. So the premise that nothing has come of genetic investigations is flat wrong.

I promised to talk about genetics being 'additive'. Personally I find this very interesting... the very distribution of heights that we find in human populations is itself good evidence that the factors influencing height are (a)many and (b)independent of each other, i.e. additive rather than multiplicative/compounding. And the evidence is that the distribution of the heights is normal. If you think this sounds shifty or weird, look up the Central Limit Theorem in statistics. There's a reason it's commonly cited as one of the fundamental theorems. The idea that many different genes, each contributing to height in it's own little way, mostly independently of the rest, collectively explain much of height is highly compatible with the distribution of observed heights.

By contrast, for example, if you look at obesity -- a well known phenomenon that is generally thought to be predominately nutritional (environment!) -- you find a log-normal distribution. This is what you get when the factors interact and reinforce one another, as so many dietary factors do. (Like using 'times' instead of 'plus' with the Central Limit Theorem). Thus there is good reason to believe that obesity is related to many interacting and compounding factors... unlike height, where the factors are additive (non-interacting). Of course, that's what genes *are*. Unlike computer programs, which will probably crash or yield errors if you change one bit, the human genome is remarkably resilient to random genetic mutations. They are literally designed to be composed linearly (additively) at the gene level, so it should not be surprising that some phenotypes involve additive composition (resulting in a normal distributio) too.

I would also like to address the comment of @sugarbabe:

I thought height was negatively associated with longevity?

I think that's true in dog breeds for example. Across species, bigger animal live longer, according to a power law. Body size, energy metabolism and lifespan. - PubMed - NCBI IIRC that effect doesn't play out at the level of individuals within a species though. A good reminder that it's ultimately neither food nor genetic influence that limits the size of creatures, but the laws of physics that they are both interacting with. There are some interesting books on this.
 
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